I've have inherited configured Kerio Control without previous experience with it.
More and more users behind that device are getting annoying Google warning about "Unusual traffic from your computer network".support.google.com/websearch/answer/86640?hl=enIs there a way to monitor traffic towards Google with Kerio?
Something like Wireshark?
I have found this page in the KB but I can't find the Context menu!!!! kb.kerio.com/product/kerio-control/logs/logging-packets-1374 .html
Am I looking in wrong way? My version is 8.5.1 build 3235.

You can create a Wireshark type capture but it would be like searching for a needle in a haystack. I'd start with the Status -> Active Hosts and look at the activity of hosts reporting this message. You can also check the HTTP log. It's likely though that the traffic is encrypted, so you may not have any luck trying to identify the issue at the gateway level.
I did some quick research and it seems that this message is usually caused by some type of malware. I'd run a security scan on those systems reporting the message.

The link you provided to Google's support page indicates that the most common cause is that somebody has Hola VPN software running which is apparently a pretty bad thing. You might also start with trying to determine if the PC's receiving this warning message have the Hola VPN software installed and follow the suggested steps for removal.

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